The invention concerns a process and an apparatus for the separation of material mixtures by way of crystallization.
In particular, the apparatus employs a substantially vertically disposed crystallization column, cooling and heating assemblages, feeding-in and withdrawal connections, pumps, valves, connected conduit tubes and a driving motor.
It is known from the prior art how to separate material mixtures by means of distillation, extraction or crystallization. Such known separation and purification techniques have many possible uses. However, it is known to one skilled in the art that for many material mixtures, such separation and purification processes are extraordinarily expensive and are often unsatisfactory.
Thus, for example, a process is known from CH-PS 501,421 for the separation of melt-liquid or of dissolved substances from material mixtures by means of a single or multi-stage fractionating crystallization procedure occurring along a wall. The starting material for such process is provided in the form of a liquid film that remains fluid during the said techniques.
The material separation following this known procedure is performed in a discontinous manner and without the aid of mechanical adjuvants. The walls of the liquid phase are provided as a ripple/percolating film. In order for cystallization to occur, the crystallizate must adhere well to such walls. Only then can a separation of the crystallizate and the mother liquor be effected. Since such adherence does not always result, the value of employing this process is limited.